VMware NSX-T Troubleshooting Fundamentals 2022

Discover why NSX-T manager won’t deploy and how to diagnose issues from insufficient host RAM/CPU and datastore space, OVA input problems, or browser compatibility, and follow VMware requirements for sizing.

Discover how to resolve NSX-T manager power-on failures caused by insufficient host resources, and how to adjust memory reservations or migrate to a host with available CPU/RAM.

Verify NSX-T manager services are online via the web console, using get services and get service http, and confirm the web interface is accessible after boot completes (about 10–15 minutes).

Troubleshoot NSX-T manager GUI access by diagnosing network issues, verifying IP connectivity and gateway reachability, correcting the VM network adapter to VLAN 251, and validating access with HTTPS.

Recover the admin password by console into the NSC's manager with the root account, then reset the admin credentials and restart the management plane api service to verify access.

Identify common host prep failures in nsx-t, such as undersized resources, version incompatibility, and stale configs, then resolve using the NSCS manager and verify with vib lists.

Troubleshoot NSX-T port groups not showing in vCenter by verifying the transport zone is assigned to the segment and added to the host and edge, enabling external connectivity.

Identify and diagnose MTU issues on transport nodes by testing VM kernel pings across Geneve-encapsulated overlays, verifying tap IPs, and ensuring jumbo MTU on the TEP VLAN.

Identify overlay issues in nsx-t by noting symptoms where VMs on nsx segments cannot talk or reach the internet, and diagnose causes like missing TEP IP or jumbo MTU settings.

Harness BFD to guarantee bidirectional host-to-host and edge tunnel health in NSX-T, enabling subsecond failover for BGP, and use BFD failures to pinpoint overlay traffic issues.

Verify BFD status across edge and transport nodes using the CLI with get BFD sessions, compare local and remote diagnostics, and supplement with packet captures on ESXi hosts for troubleshooting.

Verify tap IPs for ESXi hosts and edge nodes, validate transport node IPs and TEP connectivity, and test DHCP and VLAN configurations using GUI and CLI techniques.

Identify common NSX-T routing issues, from advertisement and redistribution problems to bgp/ospf peering, using trace flow and checks across host, edge, and physical routers.

Execute a live nsx-t routing troubleshooting lab, tracing icmp from two vms through tier one and tier zero gateways to the internet, using trace flow and logical router insights.

Troubleshoot routing and NAT translation in NSX-T by using trace flow, check route advertisement for ten and 20 networks, and verify reachability via edge and NSC components.

Test a new web dev segment in NSX-T lab using graphical user interface and command line interface to troubleshoot routing, verify BGP neighbor status, route redistribution, and end-to-end connectivity.

Troubleshoot tier zero connectivity in NSX-T by diagnosing BGP peering between the tier zero gateway and physical routers, validating VLANs, interfaces, and source addresses, and restoring established sessions.

Master how to capture packets on the edge, identify the active edge (TX zero on PT zero/one), SSH into the edge, choose interfaces, and configure capture sessions.

Learn ESXi packet capture using tcp dump uw and packet cap uw, with capture points at VM kernel, virtual switch, or uplink, saving pcap for Wireshark, featuring BFD traffic.

Verify distributed firewall hits by enabling per-rule logging, SSH into the host, and tail the DFW packet logs to confirm destination host prohibited traffic and identify the log label.

Use trace flow to identify firewall rule blocking ICMP between Apple one A and Web one A, then disable rule 1010 in infrastructure and rerun the trace to confirm connectivity.